Rigid coupling for sucker rods



Nov. s, 1938, s. .E. GRAY 2,135,812

I RIGID COUPLING FOR SUGKER RODS Original Filed June 28, 1937 INVENTR Patented Nov. 8, 1938 UNETED STATES PATENT osie Application June 28, 1937, Serial No. 150,734 Renewed April 9, 1938 2 Claims.

My invention relates to improvements in rigid 1 horizons difficulties are encountered which are coupling for sucker rods, especially adapted to prevent pump rods, cables and the like from being disconnected when the said rods and cables are rotated forward and backward in cleaning an oil string or pipe of any kind.

The principal objects of my invention are to provide a device of this character which is positive in action, simple and inexpensive in con- 10 structiom. new, novel and easily operated; which is strong, durable, reliable and of evident utility; which cannot easily get out of order and is efficient for the purposes for which it is intended; to provide a device to be used as couplings for 15 rods and cables but which cannot be disconnected by rotating the said rods and cables forward and backward in the usual manner; to provide a barrel having internal threads at its ends and an exterior wrench hex intermediate 20 said ends, the bore of the said internal threaded parts changing to inclined hopper-shaped cavities diminishing toward the mid section of said barrel and forming a narrow opening therethrough; to provide threads and threaded collars 25 for the ends of the sucker rods being coupled together, the extreme ends of said rods being ground down to blunt wedges for seating in the said hopper-shaped cavities of the said barrel and to provide plugs for holding said collars and 30 wedges rigidly in said barrel.

With these and other objects in View my invention consists of the construction, novel features and combination of parts hereinafter more fully described, illustrated in the accompanying 35 one-sheet drawing and pointed out in the claims hereto appended. Various changes in the form, proportion, size, shape, weight and minor details of construction, within the scope of my invention may be resorted to without departing from the 40 spirit or broad principle of my invention or yielding any of its benefits.

In the accompanying drawing, Figure l is an enlarged side elevation, partly in section, of the assembled device; Fig. 2 is an elevational view 45 of two of the assembled devices, the sucker rods being broken away; Fig. 3 is a sectional view on the line 3-3 of Fig. 1 and Fig. 4 is a perspective view of the end of a sucker rod showing the threads, threaded collar and wedge.

50 In the following description like reference numbers designate like parts in all the figures, and it is to be understood that the drawing is to be interpreted as being illustrative and not restrictive.

55 In the recovery of oil by pumping from deep not found in shallow production. The pump cylinder is located at the bottom of the well, and when this is at a depth of some 6500 feet the sucker rod to actuate the pump cylinder must 5 be about one and one-fourth miles long. The casing and oil string to this great depth are not perfectly straight and perpendicular but sinuous and perhaps slanting. It is frequently necessary to clean the oil string or loosen the sucker rod when it gets stuck by rotating the said rod. Rods coupled with pin and. box connections can be rotated or twisted clockwise Without disturbing the couplings but when turned counter clockwise some one of the numerous couplings in a long string usually gives way to the torsional stress and a fishing job ensues. Or when a rod of great length is twisted clock-wise until the torsional stress endangers the strength of the rod and it slips or is released suddenly, the backlash of the unwinding rod may cause it to turn counter clock-wise and uncouple the rod.

Other means of coupling rods. are in use besides the pin and box method, such as a hook and a half turn look, but this weakens the joint and causes it to break. My improved rigid coupling obviates these difiiculties as it becomes an integral part of the rod and may be turned in either direction without becoming disconnected.

While the drawing and this specification are are directed toward the use of my device in connection with solid rods, it can be easily applied to making splices or coupling wire cables and will serve as efiiciently therewith and I am therefore not restricting its use to rods alone.

One embodiment of my invention is shown as follows: The barrel or cylinder I has smooth ends 2 and a wrench hex 3 intermediate thereof. The ends 2 have interior threads 4 and unthreaded bores 5 extending inwardly from said threads 4. Extending farther inwardly as a continuation of said bores 5 are the inclined hopper-shaped cavities 6 which meet at l in a narrow slit forming an opening through the said barrel l.

Sucker rods 8 have their ends threaded at 9, the said ends are ground to form wedges at Ill with blunt points ll. Threaded collars l2 are seated on the perfect threads 9 back from the wedges It] on the ends of rods 8. Wedges l0 seat tightly in the cavities 6 and collars l2 fit snugly within the bores 5. Plugs l3 have threads M for registering with threads 4 of barrel l and are provided with wrench hexes [5.

In coupling two sucker rods or the like together the device is assembled as follows: Plugs 20 coupling.

13 with smooth inner bores l8 are slipped over the threaded ends 9 of rods 8. Collars l2 are screwed on the ends 9 of said rods 8 to proper positions relative to the wedges I0 thereon. Rods 8 are inserted into the ends of barrel I until wedges ID are seated tightly in cavities 6 and collars [2 are partly within bores 3. Plugs l3 are screwed in until inner edges l6 thereof seat firmly against the co-acting edges I! of collars l2, thus locking the coupling rigidly and making it an integral part of the sucker rod.

It will be noticed from a study of Figs. 1 and 2 that the coupling in place on the sucker rod size or shape, thereby reducing. frictional losses,

in reciprocating the sucker rods, and further, that turning or rotating the said rodsin either direction cannot unscrew or disconnect the Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A coupling of the character described, including a barrel or cylinder having threaded recesses formed within the ends thereof, the exterior of said ends having smooth walls with a wrench hex midway of the length of the barrel,

the interior of the said barrel having smooth bores at the bottoms of the threaded recesses {and extending inwardly therefrom, hoppershaped cavities meeting in a narrow slit forming an opening through the said barrel.

2. In a coupling of the character described, in combination, a barrel or cylinder with threaded recesses formed within its ends, the exterior of said ends having smooth walls with a wrench hex intermediate the lengthof the said barrel, the interior midsection of the barrel having smooth bores continuous with the said threaded recesses and changing to hopper-shaped cavities meeting in a narrow slit forming an opening through the said barrel, sucker rods threaded at their ends, portions of the threads being ground oil to form wedges with blunt points, said wedges being adapted to seat firmly in the hopper-shaped cavities of the said barrel, threaded collars for coacting with the threaded ends of the sucker rods and seating snugly in the bores of the barrel aforesaid, and smooth bored threaded plugs having wrench hexes, adapted, for registering in the said threaded recessesland coacting with the said collars for looking the sucker rods within the said barrel.

SAMUEL E. GRAY. 

